*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body{
    height: 100vh;
    display: flex;
    justify-self: center;
    align-items: center;
    background-color: pink;
}

.container{
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    width: 100vw;
}
.btn{
   border: 1px solid #fff;
   border-radius: 5px; 
   box-shadow: 3px 3px 10px rgba(0,0,0,.3);
   width: 100px;
   height: 40px;
   background-color: purple;
   color: white;
   cursor: pointer;
   margin: 0 10px;
}